Unit type tumbler switch



May 10 1933- G. A. JoVHNsoN l UNIT TYPE TUMBLER SWITCH Filed May l1'?,v 1955 N ws NV.. ...m AA s m R om, ,E G

attentati l@ iranl STATES annui UNIT ma 'rUMBLr-:n s

George A. Johnson, Trumbull, Genn., ignor to The Bryant Electric Company, Bridgeport, Conn., a corporations! Connecticut Appunuon May 1v, lets, sei-iai No. 22,090

7Claims.

` singly or in pairs or in threes in a single gang switch box behind a single gang flush or wall plate. i The switches are mounted usually in openings upon a supporting bridge of length just suiiicient to bridge across the opening of a single gang 10 switch box. Heretofore switches of this type have had their mechanism inserted in the switch casing from the rear, and the mechanism has been held in place by a iibre or metal back plate which in turn is held by a metallic securing member engaging with the sides or top of the casing.

These prior constructions have been disadvantageous for the reason that when undue pressure was exerted upon the switch handle there was likelihood that the back plate might be pushed away from the casing or might be loosened sumciently to permit undesirable movement of the contacts or other parts and of the switch mechanism and inthat way interfere with the proper` operation of the switch. It is an object of my invention to provide a unit type flush snap switch with a casing which has a solid back.

Another object of my invention is to Aprovide a unit type flush snap switch with a, solid back s0 casing and a cover which engages with the casing and is held in position upon the casing without the use of screws, rivets or other metallic securing members.

Another object oi my invention is to provide a snap switch of the above mentioned type in which the switch mechanism is held-in the casing by engagement of the cover therewith.

Another object of 'my invention is to provide a snap switch of the above type with a switch mech- 40 anism that may quickly and easilybe assembled in the casing by insertion from the front.

Another object of my invention is to provide a switch of the above type in which the switch mechanism and contacts are insertable in the front and are held in position by the engagement of the cover which in addition to its function of securing the switch parts in position also shields them from any metallic or current carrying party at the front of the switch.

Another object of my invention is toprovide a snap switch of the above type in which the cover automatically secures itself to the base when the cover is seated in its assembled position.

Other objects and advantages of my invention will become apparent to those skilled in the art as my invention is described in connection with the accompanying drawing.

In the drawing: Flgurel is a plan view looking into the interior of the switch casingwith the stationary cong tacts in place but with the movable parts of the switch mechanism removed.

Figure ilA is a longitudinalsection view of my invention with the section taken on line 2--2'01 Figure 1. v :o Figure 3 is a transverse section view oi my invention with the section taken on line 1 4 of Figure 2. s

Figure 4 is a detail view in elevation of one of the stationary contact assembly plates. 1I

Figure 5 is an elevation viewof the opposite side oi' the plate shown in Figure 4.-

Figure 6 is a side elevation view of my invention.

Referring to the drawing it will be noted that the switch mechanism of my invention ishoused' within a one-piece-hollow casing il oi insulating material which has plane side walls Ils and a solid g5 back wall Nb, and end walls lle which are each provided with lower and upper apertures for bindi ing screws of wire terminals I2a, l2b, |2c, and l2d. In the side walls los adjacent the end walls there are provided pairs of opposed slots I I and Il into 30 which may slide from the front of the casing sta tionary contact assembly plates il, Il oi' insulating material such as nbre. "These assembly plates I8, i9 are or may be substantially alike for each end. The plate I8 has upper and lower metallic 35 terminal plates 22 and 20 respectively, secured to one face thereof, with terminal screws |2a and I2b respectively screwed therein. Mounted on the insulating plate I8 are spaced stationary contacts 24 and 26 of U-shape with lateral extensions from 40 their arms passing through the insulating plate Il adjacent the top corners and into and through extensions or branches of the terminal. plates 2l and 22 respectively. To secure these contacts to their-respective terminal plates the ends of their 45 extensions may be peened over. The stationary contact assembly plate I9, although of similar construction to the assembly I8, has the stationary contacts 28 and It at the bottom of the plate instead of at the top in order that the blades 50 of the mutually insulated movable contact meinbers 32, 34 may engage with contacts 26, 30, and 24, 28 respectively in closed circuit position loi! the switch.

i -These movable bridging contact members 32. 55

Figure is an end elevation view oi' my invengo tion.'

34 may be made up from thin sheet metal stampings so as to possess resilience and engage the stationary contacts with spring pressure. These movable bridging. contacts are mounted upon lateral -outward extensions "e from the arms of a U-shaped switching member ll which may be 1 oscillated by a switch spring, 38 one end of which is engaged with the transverse portion oi' the switching member while the other end is engaged with a manually movable lever Il oi shape as shown in Fig. 2, which is pivotally mounted upon a transverse pin 42 passing through the cover 44 for the switch casing.

'This cover may be made of insulating material and may have a portion a iitting within the top :of the switch casing Il to completely close the upper end of the casing except for an aperture provided for the insulating handle Il of the manually movable lever lll. This handle and the cover form a completely closed front for the switch to prevent access oi any tool through the cover to the switch mechanism or current carrying parts.

'I'hus the cover and handle provide a "dead iront for the switch. The cover also has a central upstanding rectangular neck 44h which is may now be observed that by movement oi'the switch handle 4i and the actuating lever 40 about the pivot 42 of the handle-and lever, the

line of action of the switch spring 38 will be carried through the piane of the switching member 36 and thereby cause movement of lthe switching. member from one side of its V notch bearings to the other, and corresponding movement oi the movable switch contacts with a snap action.

One of the novel features of my invention is the means ior securing the cover to the switch casing. 'I'his means will now be described. In the side walls ills oi the switch casing adjacent i the top thereof and centrally positioned are coaxial apertures ,54 vwhich are adapted toreceive coaxial lugs 56 formed integrally and extending laterally from the sides of the cover M. These lugs or extensions may be substantially circular but beveled downwardly as illustrated in Figure 3. When applying the cover to the casing there is suflicient resiliency of the walls its to permit the beveled surfaces of the projections to act as wedges to force the walls apart until the lugs are seated in the apertures il. Thus upon applying the cover to 'the casing. the cover will snap into placeA and be maintainedthere permanently or until special tools are used to'. permit the removal oi the cover.

. I have found that insulating materiels suen es condensation products of phenols and formaldehyde,- and phenolic resins, althoughsubstantially rigid for most purposes suiiicient resiliency4 for use in making the cover and the casing of my invention. Obviously any other insulating characteristics could the-casing andcoverof my 4casing material u l t cui l 1 be used for making invention. V- :f Many modiiications within the scope oi my invention will .occur to those. skilled in the' art,

therefore I do not nmit myself to the specific iorm oi the'invention asdisclosed in the accompanying drawing.

1. In a snap switch, an insulating casing, having integral bottom and side walls,'a swinging U-shaped switching member, a pair of parallel plate-like formations of insulating material ex- 2. In a snap switch', an insulating casing having integral bottom and side walls, stationary switch contacts at opposite ends of said casing having wire terminals with screws extending into 'said casing, a swinging switching member, a pair of parallel plate-like formations of insulating material extending up from said bottom wall and having V-notch bearings for said switching member, the edges of said formation being spaced from the ends of said casing to provide roomiorV said screws, a cover for said casing, an operating member pivotally mounted in said cover and extending therethrough, and snapping mechanism for actuating said switching member. f

3. In a snap switch, an insulating casing having integral bottom and side walls, a pair of spaced plate-like insulating members parallel to one side wall, a swinging U-shaped 'switching member supported in inverted position by the ends of its legs engaging in notches in said platelike members, an insulating cover i'or said casing, snapping mechanism for actuating said contacts, and insulated operating means pivotally mounted in said cover and having :a portion moving below said switching member, said cover and operating means forming a "deadr front for the ings, and a spring connected to said operating means and said switching member, the travel of said switching member under the iniiuence of said spring being limited by its legs abutting the sides of said bearing notches.

A5. In a snap switch, an insulating casinglhaving integral back and side walls, a cover iitting within the iront of said casing, switching mechanism' within said casing, an iper-ating member of said switching mechanism extending through said cover, notched bearing members formed integrally with the bottom of said casing. and a AU-shaped switching member of' said switching mechanism supported by said bearing members, the travel of said switching member'under the inuence ot said spring being limited by its legs abutting the sides o! said bearing. notches, the edgesV of said bearing member being spaced from the ends of the casing to 4provide room. for terscrews extending in i'rom the .ends of said 6. In'a snap an insulating casing having integral bottom and side walls, stationary switchcontacts at .opposte ends of said casing having wire terminals with screws extending into said casing. a swinsinil switching member,V a pair oi parallel plate-like formations of insulating material extending up from said bottom wall and V.having V`'notch bearings for saidv switching member, the edges of said formation being spaced from the ends of said casing to provide room tor said screws, a cover tor said casing, an operating member pivotally mounted in said cover and extending therethrough. snapping mechanism for actuating said switching member, and means on said cover and casing to automatically lock said casing and cover together when said cover is inserted in the front of said casing.

7. In a snap switch. an insulating casing with integral back and side walls, a cover ntting within the front of said casing, operating means pivotaiiy mounted in said cover. notched bearing members integrally formed with the bottom oi said casing. a U-sl'iaped swiniiing switchin member supported by said bearings in inverted position by the ends o! its legs engaging in said bearings, a spring connected to said operating means and said switching member, the travel oi said switching member under the influence oi said springs being limited by its legs abutting the sides of said bearing notches, and means on said cover and casing to automatically lock said casing and cover together when said cover is inserted in tlm iront oi said casing.

GEORGE A. JOHNSON. 

